Feels Like Summer
Current overview shows weak boundary over the area that will drift away during the day. Meanwhile, up in Canada, a cold front lurks. As stated in the weekly discussion, things could get more interesting for tomorrow regarding thunderstorms.
Temperatures for today and tomorrow will be in the low to mid 90s, but we crank up the humidity, especially for tomorrow ahead of the cold front.
The hot weather and heat wave brings with it an air quality alert out of the National Weather Service, so please take extra precautions when doing outdoor activities.
It’s an Air Quality Action day for code orange with moderate particles but higher levels of Ozone.
Thunderstorms
Mt. Holly and SPC issuing chance of severe storms for today and tomorrow.
Tomorrow there will be an elevated risk, particularly in NNJ, EPA areas. CAPE could exceed 3500 J/kg with strong mid-level lapse rates. Potent shortwave trough may trigger line of storms.
Synoptic Overview
Today over the Great Lakes there are some shortwave energies that will splinte and move both south and east. It’s also possible some of the PVA we see Upstate NY/VT/NH escapes today to the south and triggers a thunderstorm in the region. Few isolated storms for this evening and the 3km NAM is shown below. I think EPA also has a chance for storms. Plenty of instability and potential energy but shortwave and winds in general won’t be disruptive enough for widespread activity.
The main feature is highlighted in purple over Canada, associated with a cold front. This will drop southeastward over the next 36 hours and will touch up stronger storms for tomorrow.
Tomorrow afternoon it is full view on our maps, along with some of the Great Lakes energy that has moved offshore.
There will be significant northwest flow driving the storms southeast. A strong line of storms, potentially severe may develop.
I am hoping to do an update tomorrow morning as well.
But for now, stay cool, stay hydrated, and keep an eye to the sky today and tomorrow.
Thank you for reading, that’s all for now!
Philadelphia Weather Authority 